u/Forget_December

So I'm creating a race of humanoid creatures that are described as very tall, but the reason for it is a different anatomic structure specifically in their legs and feet, and I'm unsure of how to describe this without it sounding like info dumping. Specifically, the length of the foot is much longer than that of human feet, and they put all of their body weight on the balls of their feet, with their heels not making contact with the ground and acting as more of a second set of knees. Is there a specific term for this type of anatomy that I could use?